On Mon, Sep 12, 2016 at 12:04:01PM +0300, Mika Westerberg wrote:

OK, I see what is going on now. When I changed handle_simple_irq to
handle_bad_irq, the IRQ core in __irq_do_set_handler() thinks the
handler is uninstalled and masks the line.

If you change handle_bad_irq to handle_simple_irq, in call to
gpiochip_irqchip_add(), does it work then?

Yes it does :), thank you for the support!